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In addition to standard features like Project Butter and support for Bluetooth Smart, the updates add in a number of custom Sony touches. The entire portfolio of Sony apps has been enhanced and upgraded: Walkman, PlayMemories, and the Battery Stamina Mode all receive a fresh coat of paint.

Sony has also loaded a custom interface as part of the update, introducing "Xperia Themes" and downloadable UI packs.

Although the Android 4.3 update has started for each of these devices, exact timing varies by market and carrier, so have a little patience if you don't see it right away.